Articles of jewelry in which multiple gems are mounted flush to one another without spaces or material being visible, are very attractive and highly desirable. For example, the gems may be set in two or more adjacent parallel rows that extend around an endless band to form a ring.
Heretofore hard stones such as diamonds have been set in this manner. In accordance with one prior art method, the diamonds are cut with grooves along their sides that engage locking ribs that extend along mounting channels in the mounting structure. The diamonds are forced under high pressure into the channels, the ribs elastically flexing out of the way enough to allow enlarged locking portions of the diamonds that are immediately above the grooves to move past the ribs so that the ribs can seat into the grooves. In this way, the diamonds are locked in place in the channels of the mounting structure.
In accordance with another method, as disclosed in U S. Pat. No. 5,072,601, the diamond is cut with a sawtooth at each side adjacent to its top, and the diamond is then forced downwardly under high pressure into the channel of the mounting structure so as to lock the diamond in place.
The diamonds are hard enough to withstand the forces exerted on them by methods of mounting such as those described above. Softer gems such as zirconium, emeralds, jade and the like are not able to withstand such forces (Diamonds have a hardness rating of about 10, ruby about 9, jade and cubic zirconium about 8 and emerald about 7. For purposes of this application, ratings of below 9 are considered softer). Efforts to mount such softer gems this way produce very high breakage rates. According, such methods as described above are not economical or practical for such softer gems.